Conference Papers
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Predictive modelling of flow in a two-dimensional intermediate-scale, heterogeneous porous media Predictive modelling of flow in a two-dimensional intermediate-scale, heterogeneous porous media
To better understand the role of sedimentary structures in flow through porous media, and to determine how small-scale laboratory-measured values of hydraulic conductivity relate to in situ values this work deterministically examines flow through simple, artificial structures constructed for a series of intermediate-scale (10 m long), two-dimensional, heterogeneous, laboratory...
Authors
Gilbert R. Barth, M. C. Hill, T.H. Illangasekare, H. Rajaram
Preface paper to the Semi-Arid Land-Surface-Atmosphere (SALSA) Program special issue Preface paper to the Semi-Arid Land-Surface-Atmosphere (SALSA) Program special issue
The Semi-Arid Land-Surface-Atmosphere Program (SALSA) is a multi-agency, multi-national research effort that seeks to evaluate the consequences of natural and human-induced environmental change in semi-arid regions. The ultimate goal of SALSA is to advance scientific understanding of the semi-arid portion of the hydrosphere-biosphere interface in order to provide reliable information for
Authors
D.C. Goodrich, A. Chehbouni, B. Goff, B. MacNish, T. Maddock, S. Moran, W.J. Shuttleworth, D. G. Williams, C. Watts, L.H. Hipps, D.I. Cooper, J. Schieldge, Y.H. Kerr, H. Arias, M. Kirkland, R. Carlos, P. Cayrol, W. Kepner, B. Jones, R. Avissar, A. Begue, J.-M. Bonnefond, G. Boulet, B. Branan, J.P. Brunel, L.C. Chen, T. Clarke, M.R. Davis, H. DeBruin, G. Dedieu, E. Elguero, W.E. Eichinger, J. Everitt, J. Garatuza-Payan, V.L. Gempko, H. Gupta, C. Harlow, O. Hartogensis, M. Helfert, C. Holifield, D. Hymer, A. Kahle, T. Keefer, S. Krishnamoorthy, J.-P. Lhomme, J.-P. Lagouarde, Seen D. Lo, D. Luquet, R. Marsett, B. Monteny, W. Ni, Y. Nouvellon, R. Pinker, C. Peters, D. Pool, J. Qi, S. Rambal, J. Rodriguez, F. Santiago, E. Sano, S.M. Schaeffer, M. Schulte, R. Scott, X. Shao, K.A. Snyder, S. Sorooshian, C.L. Unkrich, M. Whitaker, I. Yucel
Progress and over-view of current GLFT EMS project: Report on Early Mortality Syndrome Workshop Progress and over-view of current GLFT EMS project: Report on Early Mortality Syndrome Workshop
No abstract available at this time
Authors
J. Fitzsimons, S.B. Brown, D. C. Honeyfield, D. E. Tillitt
Reconnaissance survey of sulfonamide, sulfonylurea, and imidazolinone herbicides in surface streams and groundwater of the Midwestern United States Reconnaissance survey of sulfonamide, sulfonylurea, and imidazolinone herbicides in surface streams and groundwater of the Midwestern United States
The study objective was to conduct a small scale synoptic survey of representative water resources draining agricultural land for occurrence of several herbicide residues. These new classes of herbicides are commonly applied pre-emergence or post-emergence in conservation tillage systems to control grasses and broadleaf weeds in cropped and noncropped areas. Both surface water and...
Authors
T.R. Steinheimer, R.L. Pfeiffer, K.D. Scoggin, W.A. Battaglin
Redox conditions and the efficiency of chlorinated ethene biodegradation: Field studies Redox conditions and the efficiency of chlorinated ethene biodegradation: Field studies
The effect of redox conditions on the efficiency of chlorinated ethene biodegradation was investigated at two field sites. One site (NAS Cecil Field, FL) is characterized by predominantly Fe(III)-reducing conditions in the contaminant source area, grading to predominantly sulfate- reducing conditions downgradient. This sequence of redox conditions led to relatively inefficient...
Authors
F. H. Chapelle, P. M. Bradley
Redox conditions and the efficiency of chlorinated ethene biodegradation: Laboratory studies Redox conditions and the efficiency of chlorinated ethene biodegradation: Laboratory studies
The potential for biodegradation of highly reduced groundwater contaminants is greatest under aerobic conditions and least under CO2-reducing (methanogenic) conditions. Laboratory studies conducted using [1,2-14C] vinyl chloride (VC) indicate the same pattern applies to the anaerobic oxidation of relatively reduced chloroethylenes. Recent studies, showing that CH4 can be a significant...
Authors
P. M. Bradley, F. H. Chapelle
Relation between gas hydrate and physical properties at the Mallik 2L-38 research well in the Mackenzie delta Relation between gas hydrate and physical properties at the Mallik 2L-38 research well in the Mackenzie delta
As part of an interdisciplinary field program, a 1150-m deep well was drilled in the Canadian Arctic to determine, among other goals, the location, characteristics, and properties of gas hydrate. Numerous physical properties of the host sediment were measured in the laboratory and are presented in relation to the lithology and quantity of in situ gas hydrate. Profiles of measured and...
Authors
W.J. Winters, S.R. Dallimore, T. S. Collett, K.A. Jenner, J.T. Katsube, R.E. Cranston, J.F. Wright, F.M. Nixon, T. Uchida
Relations between the detection of methyl tert-butyl ether (MTBE) in surface and ground water and its content in gasoline Relations between the detection of methyl tert-butyl ether (MTBE) in surface and ground water and its content in gasoline
The relations between the content of MTBE in gasoline and the detection frequency of MTBE in ground and surface water were analyzed using the percent by volume of MTBE in gasoline provided by NIPER. For groundwater, 21 metropolitan areas had information on detection frequency and percent volume of MTBE in gasoline, while for surface water, only 9 metropolitan areas had this information...
Authors
M.J. Moran, M.J. Halde, R.M. Clawges, J.S. Zogorski
Relations of habitat-specific algal assemblages to land use and water chemistry in the Willamette Basin, Oregon Relations of habitat-specific algal assemblages to land use and water chemistry in the Willamette Basin, Oregon
Benthic algal assemblages, water chemistry, and habitat were characterized at 25 stream sites in the Willamette Basin, Oregon, during low flow in 1994. Seventy-three algal samples yielded 420 taxa - Mostly diatoms, blue-green algae, and green algae. Algal assemblages from depositional samples were strongly dominated by diatoms (76% mean relative abundance), whereas erosional samples were...
Authors
K.D. Carpenter, I.R. Waite
Reservoir characterization of marine and permafrost associated gas hydrate accumulations with downhole well logs Reservoir characterization of marine and permafrost associated gas hydrate accumulations with downhole well logs
Gas volumes that may be attributed to a gas hydrate accumulation depend on a number of reservoir parameters, one of which, gas-hydrate saturation, can be assessed with data obtained from downhole well-logging devices. This study demonstrates that electrical resistivity and acoustic transit-time downhole log data can be used to quantify the amount of gas hydrate in a sedimentary section...
Authors
T. S. Collett, Myung W. Lee
Response of geese to aircraft disturbances Response of geese to aircraft disturbances
Low-flying aircraft can affect behavior, physiology, and distribution of wildlife (Manci et al., 1988), and over time, may impact a population by reducing survival and reproductive performance. Thus, it is important to identify the particular aspects of overflights that affect animals so that management strategies can be developed to minimize adverse effects. Waterfowl are particularly...
Authors
David H. Ward, Robert A. Stehn, Dirk V. Derksen
Restoring ecological integrity of great rivers: Historical hydrographs aid in defining reference conditions for the Missouri River Restoring ecological integrity of great rivers: Historical hydrographs aid in defining reference conditions for the Missouri River
Restoring the ecological integrity of regulated large rivers necessitates characterizing the natural flow regime. We applied 'Indicators of Hydrologic Alteration' to assess the natural range of variation of the Missouri River's flow regime at 11 locations before (1929-1948) and after (1967-1996) mainstem impoundment. The 3768 km long Missouri River was divided into three sections: upper...
Authors
D.L. Galat, R. Lipkin